# Copyright 2016-2020 the openage authors. See copying.md for legal info.

""" Cutting some user interface assets into subtextures """

from ....entity_object.export.texture import TextureImage
from ....value_object.read.media.hardcoded.interface import (TOP_STRIP_PATTERN_CORNERS,
                                                             TOP_STRIP_PATTERN_SEARCH_AREA_CORNERS,
                                                             MID_STRIP_PATTERN_CORNERS,
                                                             MID_STRIP_PATTERN_SEARCH_AREA_CORNERS,
                                                             KNOWN_SUBTEX_CORNER_COORDS,
                                                             INGAME_HUD_BACKGROUNDS,
                                                             INGAME_HUD_BACKGROUNDS_SET)
from .visgrep import visgrep, crop_array


class InterfaceCutter:
    """
    Cuts interface textures into repeatable parts.
    """

    def __init__(self, idx):
        self.idx = idx

    def cut(self, image):
        """
        Create subtextures by searching for patterns at hardcoded positions.
        """

        if not isinstance(image, TextureImage):
            raise ValueError(f"we can only cut TextureImage, not '{type(image)}'")

        if is_ingame_hud_background(self.idx):
            img_data = image.get_data()

            yield self.cut_strip(img_data,
                                 TOP_STRIP_PATTERN_CORNERS,
                                 TOP_STRIP_PATTERN_SEARCH_AREA_CORNERS)

            yield self.cut_strip(img_data,
                                 MID_STRIP_PATTERN_CORNERS,
                                 MID_STRIP_PATTERN_SEARCH_AREA_CORNERS)

            for coords in KNOWN_SUBTEX_CORNER_COORDS:
                yield TextureImage(crop_array(img_data, coords))
        else:
            yield image

    def cut_strip(self, img_array, pattern_corners, search_area_corners):
        """
        Finds a horizontally tilable piece of the strip (ex. the top of the HUD).

        ||----///////////-------------///////////-------------///////////-------------///////////||
                  ^      pattern_corners     ^                    ^  where it is found last  ^
                  ^           this piece is tileable              ^

        so, cut out a subtexture:
                  ///////-------------///////////-------------////
        """

        search_area = crop_array(img_array, search_area_corners)
        pattern = crop_array(img_array, pattern_corners)

        # search for patterns, with "tolerance"
        matches = visgrep(search_area, pattern, 100000)

        if len(matches) < 2:
            raise Exception("visgrep failed to find repeating pattern in id=%d)\n" % self.idx)

        # create the found pattern texture
        return TextureImage(
            crop_array(img_array, (
                pattern_corners[0],
                pattern_corners[1],
                search_area_corners[0] + matches[-1].point[0],
                pattern_corners[3]
            ))
        )


def ingame_hud_background_index(idx):
    """
    Index in the hardcoded list of the known ingame hud backgrounds to match the civ.
    """
    return INGAME_HUD_BACKGROUNDS.index(int(idx))


def is_ingame_hud_background(idx):
    """
    True if in the hardcoded list of the known ingame hud backgrounds.
    """
    return int(idx) in INGAME_HUD_BACKGROUNDS_SET
